There were sixty million[0] PSN accounts. This is impressive, and amounts to (judging by a quick search) the largest-scale ID (and possibly credit-card) theft ever [Not so, see child comment]. Not even factoring in credit card details, the usernames, emails, addresses, ages, passwords, mother's maiden names, favourite pets, of sixty million people is worth a hell of a lot.
I have to wonder how much data that is, in terms of storage. How could you even take that without someone noticing?
Hats off to whoever it was. Now, I'm off to change my passwords. Thank Christ I had the sense not to use a credit card to buy from PSN.
[0] http://www.derangedshaman.com/2011/01/06/sonys-60-million-ps...
[edit] On a related note, paypal refuses to let my change my password to something longer than 20 characters - or have spaces in my password. Why is this the case? Surely the only thing that an upper limit on the length of a password does is help the attacker.